raise tax revenue from a part of the economy where you want to discourage activity and use that for education. >> the private sector is sitting on more uninvested cash. this is not stock, not money given to owners. >> firms sitting on cash waiting to invest. they are waiting for cues. tacking them, taxing carbon would help give cues to drive investment into clean energy. another way -- >> they are very skeptical about clean energy. you also have to realize it's a terrible investment for the past decade. this is not an easy problem. >> one of the problems is lack of markets. the government could do a lot to fix that by consuming clean energy and vehicles. the federal government is in the u.s. is the single largest consumer of clean energy. if you add state and federal spending, if you look at the percentage of the gdp, the public sector, it's over 1%. >> and what helps is lots of natural gas in the united states. so there's even an alignment with what i think are going to be the economic interests. >> so the problem is that will probably make the unemployment problem worse and that lowers the